AM? Well,
I have not tried. You gotta reduce input power a lot. 2-3W carrier
output would be appropiate. Feed plate and screen through a modulation
iron of around 7-8 kohms secondary impedance. Avoid AM on 80M
during dark hours in EU, there ain't room enuff.
A little warning: Lethal voltages are present in this circuit. Be careful. Do not omit
the output-to-ground choke. The -100V present at the key is not
dangerous if the resistor values in the schematics are used and
are of adequate quality and voltage rating.
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The circuit could use a 6GW8/ECL86 but the high
mu triode section is a tad hard to tame. It requires less bias
voltage. I'll try another glowbug with this tube but with a Colpitts
oscillator instead. Stay tuned, I will
make a 6GW8/ECL86 bug also, perhaps after I have finished the
Eurobug (EL83+EL34).
This glowbug has been on air for some time now and
the reports are good, no chirp and no clicks. "Very good
sound" is the normal report.
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